param.h for USERSTACK=2

Makefile

@@ -61,7 +61,7 @@ endif
 
 # riscv64-unknown-elf- or riscv64-linux-gnu-
 # perhaps in /opt/riscv/bin
-TOOLPREFIX = /opt/riscv/bin/riscv64-unknown-elf-
+#TOOLPREFIX = 
 
 # Try to infer the correct TOOLPREFIX if not set
 ifndef TOOLPREFIX
@@ -276,9 +276,6 @@ endif
 fs.img: mkfs/mkfs README $(UEXTRA) $(UPROGS)
 	mkfs/mkfs fs.img README $(UEXTRA) $(UPROGS)
 
-newfs.img: 
-	-mv -f fs.img fs.img.bk
-
 -include kernel/*.d user/*.d
 
 clean:
@@ -286,7 +283,7 @@ clean:
 	*/*.o */*.d */*.asm */*.sym \
 	$U/initcode $U/initcode.out $U/usys.S $U/_* \
 	$K/kernel \
-	mkfs/mkfs fs.img fs.img.bk .gdbinit __pycache__ xv6.out* \
+	mkfs/mkfs fs.img .gdbinit __pycache__ xv6.out* \
 	ph barrier
 
 # try to generate a unique GDB port
@@ -315,12 +312,7 @@ QEMUOPTS += -netdev user,id=net0,hostfwd=udp::$(FWDPORT1)-:2000,hostfwd=udp::$(F
 QEMUOPTS += -device e1000,netdev=net0,bus=pcie.0
 endif
 
-# makes a new fs.img
-qemu: newfs.img $K/kernel fs.img
-	$(QEMU) $(QEMUOPTS)
-
-# runs with existing fs.img, if present
-qemu-fs: $K/kernel fs.img
+qemu: $K/kernel fs.img
 	$(QEMU) $(QEMUOPTS)
 
 .gdbinit: .gdbinit.tmpl-riscv

README

@@ -31,6 +31,9 @@ Rafael Ubal, Amane Uehara, Pablo Ventura, Xi Wang, WaheedHafez,
 Keiichi Watanabe, Lucas Wolf, Nicolas Wolovick, wxdao, Grant Wu, x653,
 Jindong Zhang, Icenowy Zheng, ZhUyU1997, and Zou Chang Wei.
 
+The code in the files that constitute xv6 is
+Copyright 2006-2024 Frans Kaashoek, Robert Morris, and Russ Cox.
+
 ERROR REPORTS
 
 Please send errors and suggestions to Frans Kaashoek and Robert Morris

conf/lab.mk

@@ -1 +1 @@
-LAB=lock
+LAB=util

grade-lab-lock

@@ -1,66 +0,0 @@
-#!/usr/bin/env python3
-
-import re
-from gradelib import *
-
-r = Runner(save("xv6.out"))
-
-@test(0, "running kalloctest")
-def test_kalloctest():
-    r.run_qemu(shell_script([
-        'kalloctest'
-    ]), timeout=300)
-    
-@test(10, "kalloctest: test1", parent=test_kalloctest)
-def test_kalloctest_test1():
-    r.match('^test1 OK$')
-    
-@test(10, "kalloctest: test2", parent=test_kalloctest)
-def test_kalloctest_test2():
-    r.match('^test2 OK$')
-
-@test(10, "kalloctest: test3", parent=test_kalloctest)
-def test_kalloctest_test3():
-    r.match('^test3 OK$')
-
-@test(10, "kalloctest: sbrkmuch")
-def test_sbrkmuch():
-    r.run_qemu(shell_script([
-        'usertests sbrkmuch'
-    ]), timeout=90)
-    r.match('^ALL TESTS PASSED$')
-
-@test(0, "running bcachetest")
-def test_bcachetest():
-    r.run_qemu(shell_script([
-        'bcachetest'
-    ]), timeout=150)
-    
-@test(20, "bcachetest: test0", parent=test_bcachetest)
-def test_bcachetest_test0():
-    r.match('^test0: OK$')
-    
-@test(10, "bcachetest: test1", parent=test_bcachetest)
-def test_bcachetest_test1():
-    r.match('^test1 OK$')
-
-@test(10, "bcachetest: test2", parent=test_bcachetest)
-def test_bcachetest_test2():
-    r.match('^test2 OK$')
-
-@test(10, "bcachetest: test3", parent=test_bcachetest)
-def test_bcachetest_test3():
-    r.match('^test3 OK$')
-
-@test(19, "usertests")
-def test_usertests():
-    r.run_qemu(shell_script([
-        'usertests -q'
-    ]), timeout=300)
-    r.match('^ALL TESTS PASSED$')
-
-@test(1, "time")
-def test_time():
-    check_time()
-
-run_tests()

grade-lab-util

@@ -0,0 +1,105 @@
+#!/usr/bin/env python3
+
+import re
+from gradelib import *
+
+r = Runner(save("xv6.out"))
+
+@test(5, "sleep, no arguments")
+def test_sleep_no_args():
+    r.run_qemu(shell_script([
+        'sleep'
+    ]))
+    r.match(no=["exec .* failed", "$ sleep\n$"])
+
+@test(5, "sleep, returns")
+def test_sleep_no_args():
+    r.run_qemu(shell_script([
+        'sleep',
+        'echo OK'
+    ]))
+    r.match('^OK$', no=["exec .* failed", "$ sleep\n$"])
+
+@test(10, "sleep, makes syscall")
+def test_sleep():
+    r.run_qemu(shell_script([
+        'sleep 10',
+        'echo FAIL'
+    ]), stop_breakpoint('sys_sleep'))
+    r.match('\\$ sleep 10', no=['FAIL'])
+
+@test(20, "pingpong")
+def test_pingpong():
+    r.run_qemu(shell_script([
+        'pingpong', 'echo OK'
+    ]))
+    r.match('^\\d+: received ping$', '^\\d+: received pong$', '^OK$')
+
+@test(20, "primes")
+def test_primes():
+    r.run_qemu(shell_script([
+        'primes', 'echo OK'
+    ]))
+    args = ['prime %d' % i for i in [2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 211, 223, 227, 229, 233, 239, 241, 251, 257, 263, 269]]
+    args.append('^OK$')
+    r.match(*args)
+
+@test(10, "find, in current directory")
+def test_find_curdir():
+    fn = random_str()
+    r.run_qemu(shell_script([
+        'echo > %s' % fn,
+        'find . %s' % fn
+    ]))
+    r.match('./%s' % fn)
+    r.match(no=["./README", "README"])
+
+@test(10, "find, in sub-directory")
+def test_find_curdir():
+    dd = random_str()
+    fn = random_str()
+    r.run_qemu(shell_script([
+        'echo > %s' % fn,
+        'mkdir %s' % dd,
+        'echo > %s/%s' % (dd, fn),
+        'find %s %s' % (dd, fn)
+    ]))
+    r.match('%s/%s' % (dd, fn))
+    r.match(no=['./%s' % fn])
+
+@test(10, "find, recursive")
+def test_find_recursive():
+    needle = random_str()
+    dirs = [random_str() for _ in range(3)]
+    r.run_qemu(shell_script([
+        'mkdir %s' % dirs[0],
+        'echo > %s/%s' % (dirs[0], needle),
+        'mkdir %s/%s' % (dirs[0], dirs[1]),
+        'echo > %s/%s/%s' % (dirs[0], dirs[1], needle),
+        'mkdir %s' % dirs[2],
+        'echo > %s/%s' % (dirs[2], needle),
+        'find . %s' % needle
+    ]))
+    r.match('./%s/%s' % (dirs[0], needle),
+            './%s/%s/%s' % (dirs[0], dirs[1], needle),
+            './%s/%s' % (dirs[2], needle))
+
+@test(10, "xargs")
+def test_xargs():
+    r.run_qemu(shell_script([
+        'sh < xargstest.sh',
+        'echo DONE',
+    ], 'DONE'))
+    matches = re.findall("hello", r.qemu.output)
+    assert_equal(len(matches), 3, "Number of appearances of 'hello'")
+
+@test(9, "xargs, multi-line echo")
+def test_xargs_multiline():
+    r.run_qemu(shell_script(['(echo 1 ; echo 2) | xargs echo']))
+    r.match('^1$', '^2$')
+
+@test(1, "time")
+def test_time():
+    check_time()
+    
+run_tests()

kernel/defs.h

@@ -1,7 +1,3 @@
-#ifdef LAB_MMAP
-typedef unsigned long size_t;
-typedef long int off_t;
-#endif
 struct buf;
 struct context;
 struct file;
@@ -121,10 +117,6 @@ void            initlock(struct spinlock*, char*);
 void            release(struct spinlock*);
 void            push_off(void);
 void            pop_off(void);
-int             atomic_read4(int *addr);
-#ifdef LAB_LOCK
-void            freelock(struct spinlock*);
-#endif
 
 // sleeplock.c
 void            acquiresleep(struct sleeplock*);
@@ -181,12 +173,6 @@ uint64          walkaddr(pagetable_t, uint64);
 int             copyout(pagetable_t, uint64, char *, uint64);
 int             copyin(pagetable_t, char *, uint64, uint64);
 int             copyinstr(pagetable_t, char *, uint64, uint64);
-#if defined(LAB_PGTBL) || defined(SOL_MMAP)
-void            vmprint(pagetable_t);
-#endif
-#ifdef LAB_PGTBL
-pte_t*          pgpte(pagetable_t, uint64);
-#endif
 
 // plic.c
 void            plicinit(void);
@@ -201,39 +187,3 @@ void            virtio_disk_intr(void);
 
 // number of elements in fixed-size array
 #define NELEM(x) (sizeof(x)/sizeof((x)[0]))
-
-
-
-#ifdef LAB_PGTBL
-// vmcopyin.c
-int             copyin_new(pagetable_t, char *, uint64, uint64);
-int             copyinstr_new(pagetable_t, char *, uint64, uint64);
-#endif
-
-#ifdef LAB_LOCK
-// stats.c
-void            statsinit(void);
-void            statsinc(void);
-
-// sprintf.c
-int             snprintf(char*, unsigned long, const char*, ...);
-#endif
-
-#ifdef KCSAN
-void            kcsaninit();
-#endif
-
-#ifdef LAB_NET
-// pci.c
-void            pci_init();
-
-// e1000.c
-void            e1000_init(uint32 *);
-void            e1000_intr(void);
-int             e1000_transmit(char *, int);
-
-// net.c
-void            netinit(void);
-void            net_rx(char *buf, int len);
-
-#endif

kernel/file.h

@@ -38,4 +38,3 @@ struct devsw {
 extern struct devsw devsw[];
 
 #define CONSOLE 1
-#define STATS   2

kernel/fs.c

@@ -295,11 +295,11 @@ ilock(struct inode *ip)
   struct buf *bp;
   struct dinode *dip;
 
-  if(ip == 0 || atomic_read4(&ip->ref) < 1)
+  if(ip == 0 || ip->ref < 1)
     panic("ilock");
 
   acquiresleep(&ip->lock);
-  
+
   if(ip->valid == 0){
     bp = bread(ip->dev, IBLOCK(ip->inum, sb));
     dip = (struct dinode*)bp->data + ip->inum%IPB;
@@ -320,7 +320,7 @@ ilock(struct inode *ip)
 void
 iunlock(struct inode *ip)
 {
-  if(ip == 0 || !holdingsleep(&ip->lock) || atomic_read4(&ip->ref) < 1)
+  if(ip == 0 || !holdingsleep(&ip->lock) || ip->ref < 1)
     panic("iunlock");
 
   releasesleep(&ip->lock);
@@ -416,6 +416,7 @@ bmap(struct inode *ip, uint bn)
     brelse(bp);
     return addr;
   }
+
   panic("bmap: out of range");
 }
 
@@ -446,7 +447,7 @@ itrunc(struct inode *ip)
     bfree(ip->dev, ip->addrs[NDIRECT]);
     ip->addrs[NDIRECT] = 0;
   }
-  
+
   ip->size = 0;
   iupdate(ip);
 }

kernel/kcsan.c

@@ -1,323 +0,0 @@
-#include "types.h"
-#include "param.h"
-#include "memlayout.h"
-#include "spinlock.h"
-#include "riscv.h"
-#include "proc.h"
-#include "defs.h"
-
-//
-// Race detector using gcc's thread sanitizer. It delays all stores
-// and loads and monitors if any other CPU is using the same address.
-// If so, we have a race and print out the backtrace of the thread
-// that raced and the thread that set the watchpoint.
-//
-
-//
-// To run with kcsan:
-// make clean
-// make KCSAN=1 qemu
-//
-
-// The number of watch points.
-#define NWATCH (NCPU)
-
-// The number of cycles to delay stores, whatever that means on qemu.
-//#define DELAY_CYCLES 20000
-#define DELAY_CYCLES 200000
-
-#define MAXTRACE 20
-
-int
-trace(uint64 *trace, int maxtrace)
-{
-  uint64 i = 0;
-  
-  push_off();
-  
-  uint64 fp = r_fp();
-  uint64 ra, low = PGROUNDDOWN(fp) + 16, high = PGROUNDUP(fp);
-
-  while(!(fp & 7) && fp >= low && fp < high){
-    ra = *(uint64*)(fp - 8);
-    fp = *(uint64*)(fp - 16);
-    trace[i++] = ra;
-    if(i >= maxtrace)
-      break;
-  }
-
-  pop_off();
-  
-  return i;
-}
-
-struct watch {
-  uint64 addr;
-  int write;
-  int race;
-  uint64 trace[MAXTRACE];
-  int tracesz;
-};
-  
-struct {
-  struct spinlock lock;
-  struct watch points[NWATCH];
-  int on;
-} tsan;
-
-static struct watch*
-wp_lookup(uint64 addr)
-{
-  for(struct watch *w = &tsan.points[0]; w < &tsan.points[NWATCH]; w++) {
-    if(w->addr == addr) {
-      return w;
-    }
-  }
-  return 0;
-}
-
-static int
-wp_install(uint64 addr, int write)
-{
-  for(struct watch *w = &tsan.points[0]; w < &tsan.points[NWATCH]; w++) {
-    if(w->addr == 0) {
-      w->addr = addr;
-      w->write = write;
-      w->tracesz = trace(w->trace, MAXTRACE);
-      return 1;
-    }
-  }
-  panic("wp_install");
-  return 0;
-}
-
-static void
-wp_remove(uint64 addr)
-{
-  for(struct watch *w = &tsan.points[0]; w < &tsan.points[NWATCH]; w++) {
-    if(w->addr == addr) {
-      w->addr = 0;
-      w->tracesz = 0;
-      return;
-    }
-  }
-  panic("remove");
-}
-
-static void
-printtrace(uint64 *t, int n)
-{
-  int i;
-  
-  for(i = 0; i < n; i++) {
-    printf("%p\n", (void*) t[i]);
-  }
-}
-
-static void
-race(char *s, struct watch *w) {
-  uint64 t[MAXTRACE];
-  int n;
-  
-  n = trace(t, MAXTRACE);
-  printf("== race detected ==\n");
-  printf("backtrace for racing %s\n", s);
-  printtrace(t, n);
-  printf("backtrace for watchpoint:\n");
-  printtrace(w->trace, w->tracesz);
-  printf("==========\n");
-}
-
-// cycle counter
-static inline uint64
-r_cycle()
-{
-  uint64 x;
-  asm volatile("rdcycle %0" : "=r" (x) );
-  return x;
-}
-
-static void delay(void) __attribute__((noinline));
-static void delay() {
-  uint64 stop = r_cycle() + DELAY_CYCLES;
-  uint64 c = r_cycle();
-  while(c < stop) {
-    c = r_cycle();
-  }
-}
-
-static void
-kcsan_read(uint64 addr, int sz)
-{
-  struct watch *w;
-  
-  acquire(&tsan.lock);
-  if((w = wp_lookup(addr)) != 0) {
-    if(w->write) {
-      race("load", w);
-    }
-    release(&tsan.lock);
-    return;
-  }
-  release(&tsan.lock);
-}
-
-static void
-kcsan_write(uint64 addr, int sz)
-{
-  struct watch *w;
-  
-  acquire(&tsan.lock);
-  if((w = wp_lookup(addr)) != 0) {
-    race("store", w);
-    release(&tsan.lock);
-  }
-
-  // no watchpoint; try to install one
-  if(wp_install(addr, 1)) {
-
-    release(&tsan.lock);
-
-    // XXX maybe read value at addr before and after delay to catch
-    // races of unknown origins (e.g., device).
-
-    delay(); 
-
-    acquire(&tsan.lock);
-
-    wp_remove(addr);
-  }
-  release(&tsan.lock);
-}
-
-// tsan.on will only have effect with "make KCSAN=1"
-void
-kcsaninit(void)
-{
-  initlock(&tsan.lock, "tsan");
-  tsan.on = 1;
-  __sync_synchronize();
-}
-
-//
-// Calls inserted by compiler into kernel binary, except for this file.
-//
-
-void
-__tsan_init(void)
-{
-}
-
-void
-__tsan_read1(uint64 addr)
-{
-  if(!tsan.on)
-    return;
-  // kcsan_read(addr, 1);
-}
-
-void
-__tsan_read2(uint64 addr)
-{
-  if(!tsan.on)
-    return;
-  kcsan_read(addr, 2);
-}
-
-void
-__tsan_read4(uint64 addr)
-{
-  if(!tsan.on)
-    return;
-  kcsan_read(addr, 4);
-}
-
-void
-__tsan_read8(uint64 addr)
-{
-  if(!tsan.on)
-    return;
-  kcsan_read(addr, 8);
-}
-
-void
-__tsan_read_range(uint64 addr, uint64 size)
-{
-  if(!tsan.on)
-    return;
-  kcsan_read(addr, size);
-}
-
-void
-__tsan_write1(uint64 addr)
-{
-  if(!tsan.on)
-    return;
-  // kcsan_write(addr, 1);
-}
-
-void
-__tsan_write2(uint64 addr)
-{
-  if(!tsan.on)
-    return;
-  kcsan_write(addr, 2);
-}
-
-void
-__tsan_write4(uint64 addr)
-{
-  if(!tsan.on)
-    return;
-  kcsan_write(addr, 4);
-}
-
-void
-__tsan_write8(uint64 addr)
-{
-  if(!tsan.on)
-    return;
-  kcsan_write(addr, 8);
-}
-
-void
-__tsan_write_range(uint64 addr, uint64 size)
-{
-  if(!tsan.on)
-    return;
-  kcsan_write(addr, size);
-}
-
-void
-__tsan_atomic_thread_fence(int order)
-{
-  __sync_synchronize();
-}
-
-uint32
-__tsan_atomic32_load(uint *ptr, uint *val, int order)
-{
-  uint t;
-  __atomic_load(ptr, &t, __ATOMIC_SEQ_CST);
-  return t;
-}
-
-void
-__tsan_atomic32_store(uint *ptr, uint val, int order)
-{
-  __atomic_store(ptr, &val, __ATOMIC_SEQ_CST);
-}
-
-// We don't use this
-void
-__tsan_func_entry(uint64 pc)
-{
-}
-
-// We don't use this
-void
-__tsan_func_exit(void)
-{
-}
-
-

kernel/main.c

@@ -12,9 +12,6 @@ main()
 {
   if(cpuid() == 0){
     consoleinit();
-#if defined(LAB_LOCK)
-    statsinit();
-#endif
     printfinit();
     printf("\n");
     printf("xv6 kernel is booting\n");
@@ -31,17 +28,11 @@ main()
     iinit();         // inode table
     fileinit();      // file table
     virtio_disk_init(); // emulated hard disk
-#ifdef LAB_NET
-    pci_init();
-#endif    
     userinit();      // first user process
-#ifdef KCSAN
-    kcsaninit();
-#endif
     __sync_synchronize();
     started = 1;
   } else {
-    while(atomic_read4((int *) &started) == 0)
+    while(started == 0)
       ;
     __sync_synchronize();
     printf("hart %d starting\n", cpuid());

kernel/param.h

@@ -1,4 +1,8 @@
-#define NPROC        64  // maximum number of processes
+#ifdef LAB_FS
+#define NPROC        10  // maximum number of processes
+#else
+#define NPROC        64  // maximum number of processes (speedsup bigfile)
+#endif
 #define NCPU          8  // maximum number of CPUs
 #define NOFILE       16  // open files per process
 #define NFILE       100  // open files per system
@@ -9,7 +13,21 @@
 #define MAXOPBLOCKS  10  // max # of blocks any FS op writes
 #define LOGSIZE      (MAXOPBLOCKS*3)  // max data blocks in on-disk log
 #define NBUF         (MAXOPBLOCKS*3)  // size of disk block cache
-#define FSSIZE       2000  // size of file system in blocks
+#ifdef LAB_FS
+#define FSSIZE       200000  // size of file system in blocks
+#else
+#ifdef LAB_LOCK
+#define FSSIZE       10000  // size of file system in blocks
+#else
+#define FSSIZE       2000   // size of file system in blocks
+#endif
+#endif
 #define MAXPATH      128   // maximum file path name
-#define USERSTACK    1     // user stack pages
+
+#ifdef LAB_UTIL
+#define USERSTACK    2     // user stack pages
+#else
+#define USERSTACK    1     // user stack pages
+#endif
+
 

kernel/pipe.c

@@ -68,9 +68,6 @@ pipeclose(struct pipe *pi, int writable)
   }
   if(pi->readopen == 0 && pi->writeopen == 0){
     release(&pi->lock);
-#ifdef LAB_LOCK
-    freelock(&pi->lock);
-#endif    
     kfree((char*)pi);
   } else
     release(&pi->lock);

kernel/spinlock.c

@@ -8,52 +8,12 @@
 #include "proc.h"
 #include "defs.h"
 
-#ifdef LAB_LOCK
-#define NLOCK 500
-
-static struct spinlock *locks[NLOCK];
-struct spinlock lock_locks;
-
-void
-freelock(struct spinlock *lk)
-{
-  acquire(&lock_locks);
-  int i;
-  for (i = 0; i < NLOCK; i++) {
-    if(locks[i] == lk) {
-      locks[i] = 0;
-      break;
-    }
-  }
-  release(&lock_locks);
-}
-
-static void
-findslot(struct spinlock *lk) {
-  acquire(&lock_locks);
-  int i;
-  for (i = 0; i < NLOCK; i++) {
-    if(locks[i] == 0) {
-      locks[i] = lk;
-      release(&lock_locks);
-      return;
-    }
-  }
-  panic("findslot");
-}
-#endif
-
 void
 initlock(struct spinlock *lk, char *name)
 {
   lk->name = name;
   lk->locked = 0;
   lk->cpu = 0;
-#ifdef LAB_LOCK
-  lk->nts = 0;
-  lk->n = 0;
-  findslot(lk);
-#endif  
 }
 
 // Acquire the lock.
@@ -65,21 +25,12 @@ acquire(struct spinlock *lk)
   if(holding(lk))
     panic("acquire");
 
-#ifdef LAB_LOCK
-    __sync_fetch_and_add(&(lk->n), 1);
-#endif      
-
   // On RISC-V, sync_lock_test_and_set turns into an atomic swap:
   //   a5 = 1
   //   s1 = &lk->locked
   //   amoswap.w.aq a5, a5, (s1)
-  while(__sync_lock_test_and_set(&lk->locked, 1) != 0) {
-#ifdef LAB_LOCK
-    __sync_fetch_and_add(&(lk->nts), 1);
-#else
-   ;
-#endif
-  }
+  while(__sync_lock_test_and_set(&lk->locked, 1) != 0)
+    ;
 
   // Tell the C compiler and the processor to not move loads or stores
   // past this point, to ensure that the critical section's memory
@@ -157,61 +108,3 @@ pop_off(void)
   if(c->noff == 0 && c->intena)
     intr_on();
 }
-
-// Read a shared 32-bit value without holding a lock
-int
-atomic_read4(int *addr) {
-  uint32 val;
-  __atomic_load(addr, &val, __ATOMIC_SEQ_CST);
-  return val;
-}
-
-#ifdef LAB_LOCK
-int
-snprint_lock(char *buf, int sz, struct spinlock *lk)
-{
-  int n = 0;
-  if(lk->n > 0) {
-    n = snprintf(buf, sz, "lock: %s: #test-and-set %d #acquire() %d\n",
-                 lk->name, lk->nts, lk->n);
-  }
-  return n;
-}
-
-int
-statslock(char *buf, int sz) {
-  int n;
-  int tot = 0;
-
-  acquire(&lock_locks);
-  n = snprintf(buf, sz, "--- lock kmem/bcache stats\n");
-  for(int i = 0; i < NLOCK; i++) {
-    if(locks[i] == 0)
-      break;
-    if(strncmp(locks[i]->name, "bcache", strlen("bcache")) == 0 ||
-       strncmp(locks[i]->name, "kmem", strlen("kmem")) == 0) {
-      tot += locks[i]->nts;
-      n += snprint_lock(buf +n, sz-n, locks[i]);
-    }
-  }
-  
-  n += snprintf(buf+n, sz-n, "--- top 5 contended locks:\n");
-  int last = 100000000;
-  // stupid way to compute top 5 contended locks
-  for(int t = 0; t < 5; t++) {
-    int top = 0;
-    for(int i = 0; i < NLOCK; i++) {
-      if(locks[i] == 0)
-        break;
-      if(locks[i]->nts > locks[top]->nts && locks[i]->nts < last) {
-        top = i;
-      }
-    }
-    n += snprint_lock(buf+n, sz-n, locks[top]);
-    last = locks[top]->nts;
-  }
-  n += snprintf(buf+n, sz-n, "tot= %d\n", tot);
-  release(&lock_locks);  
-  return n;
-}
-#endif

kernel/spinlock.h

@@ -5,9 +5,5 @@ struct spinlock {
   // For debugging:
   char *name;        // Name of lock.
   struct cpu *cpu;   // The cpu holding the lock.
-#ifdef LAB_LOCK
-  int nts;
-  int n;
-#endif
 };
 

kernel/sprintf.c

@@ -1,88 +0,0 @@
-#include <stdarg.h>
-
-#include "types.h"
-#include "param.h"
-#include "spinlock.h"
-#include "sleeplock.h"
-#include "fs.h"
-#include "file.h"
-#include "riscv.h"
-#include "defs.h"
-
-static char digits[] = "0123456789abcdef";
-
-static int
-sputc(char *s, char c)
-{
-  *s = c;
-  return 1;
-}
-
-static int
-sprintint(char *s, int xx, int base, int sign)
-{
-  char buf[16];
-  int i, n;
-  uint x;
-
-  if(sign && (sign = xx < 0))
-    x = -xx;
-  else
-    x = xx;
-
-  i = 0;
-  do {
-    buf[i++] = digits[x % base];
-  } while((x /= base) != 0);
-
-  if(sign)
-    buf[i++] = '-';
-
-  n = 0;
-  while(--i >= 0)
-    n += sputc(s+n, buf[i]);
-  return n;
-}
-
-int
-snprintf(char *buf, unsigned long sz, const char *fmt, ...)
-{
-  va_list ap;
-  int i, c;
-  int off = 0;
-  char *s;
-
-  va_start(ap, fmt);
-  for(i = 0; off < sz && (c = fmt[i] & 0xff) != 0; i++){
-    if(c != '%'){
-      off += sputc(buf+off, c);
-      continue;
-    }
-    c = fmt[++i] & 0xff;
-    if(c == 0)
-      break;
-    switch(c){
-    case 'd':
-      off += sprintint(buf+off, va_arg(ap, int), 10, 1);
-      break;
-    case 'x':
-      off += sprintint(buf+off, va_arg(ap, int), 16, 1);
-      break;
-    case 's':
-      if((s = va_arg(ap, char*)) == 0)
-        s = "(null)";
-      for(; *s && off < sz; s++)
-        off += sputc(buf+off, *s);
-      break;
-    case '%':
-      off += sputc(buf+off, '%');
-      break;
-    default:
-      // Print unknown % sequence to draw attention.
-      off += sputc(buf+off, '%');
-      off += sputc(buf+off, c);
-      break;
-    }
-  }
-  return off;
-}

kernel/start.c

@@ -32,11 +32,6 @@ start()
   w_mideleg(0xffff);
   w_sie(r_sie() | SIE_SEIE | SIE_STIE | SIE_SSIE);
 
-#ifdef KCSAN
-  // allow supervisor to read cycle counter register
-  w_mcounteren(r_mcounteren()|0x3);
-#endif
-  
   // configure Physical Memory Protection to give supervisor mode
   // access to all of physical memory.
   w_pmpaddr0(0x3fffffffffffffull);

kernel/stats.c

@@ -1,69 +0,0 @@
-#include <stdarg.h>
-
-#include "types.h"
-#include "param.h"
-#include "spinlock.h"
-#include "sleeplock.h"
-#include "fs.h"
-#include "file.h"
-#include "riscv.h"
-#include "defs.h"
-
-#define BUFSZ 4096
-static struct {
-  struct spinlock lock;
-  char buf[BUFSZ];
-  int sz;
-  int off;
-} stats;
-
-int statscopyin(char*, int);
-int statslock(char*, int);
-  
-int
-statswrite(int user_src, uint64 src, int n)
-{
-  return -1;
-}
-
-int
-statsread(int user_dst, uint64 dst, int n)
-{
-  int m;
-
-  acquire(&stats.lock);
-
-  if(stats.sz == 0) {
-#ifdef LAB_PGTBL
-    stats.sz = statscopyin(stats.buf, BUFSZ);
-#endif
-#ifdef LAB_LOCK
-    stats.sz = statslock(stats.buf, BUFSZ);
-#endif
-  }
-  m = stats.sz - stats.off;
-
-  if (m > 0) {
-    if(m > n)
-      m  = n;
-    if(either_copyout(user_dst, dst, stats.buf+stats.off, m) != -1) {
-      stats.off += m;
-    }
-  } else {
-    m = -1;
-    stats.sz = 0;
-    stats.off = 0;
-  }
-  release(&stats.lock);
-  return m;
-}
-
-void
-statsinit(void)
-{
-  initlock(&stats.lock, "stats");
-
-  devsw[STATS].read = statsread;
-  devsw[STATS].write = statswrite;
-}
-

kernel/virtio_disk.c

@@ -212,28 +212,6 @@ alloc3_desc(int *idx)
   return 0;
 }
 
-#ifdef LAB_LOCK
-//
-// check that there are at most NBUF distinct
-// struct buf's, which the lock lab requires.
-//
-static struct buf *xbufs[NBUF];
-static void
-checkbuf(struct buf *b)
-{
-  for(int i = 0; i < NBUF; i++){
-    if(xbufs[i] == b){
-      return;
-    }
-    if(xbufs[i] == 0){
-      xbufs[i] = b;
-      return;
-    }
-  }
-  panic("more than NBUF bufs");
-}
-#endif
-
 void
 virtio_disk_rw(struct buf *b, int write)
 {
@@ -241,10 +219,6 @@ virtio_disk_rw(struct buf *b, int write)
 
   acquire(&disk.vdisk_lock);
 
-#ifdef LAB_LOCK
-  checkbuf(b);
-#endif
-
   // the spec's Section 5.2 says that legacy block operations use
   // three descriptors: one for type/reserved/sector, one for the
   // data, one for a 1-byte status result.

user/bcachetest.c

@@ -1,400 +0,0 @@
-#include "kernel/fcntl.h"
-#include "kernel/param.h"
-#include "kernel/types.h"
-#include "kernel/stat.h"
-#include "kernel/riscv.h"
-#include "kernel/fs.h"
-#include "user/user.h"
-
-void test0();
-void test1();
-void test2();
-void test3();
-
-#define SZ 4096
-char buf[SZ];
-
-int
-main(int argc, char *argv[])
-{
-  test0();
-  test1();
-  test2();
-  test3();
-  exit(0);
-}
-
-void
-createfile(char *file, int nblock)
-{
-  int fd;
-  char buf[BSIZE];
-  int i;
-  
-  fd = open(file, O_CREATE | O_RDWR);
-  if(fd < 0){
-    printf("createfile %s failed\n", file);
-    exit(-1);
-  }
-  for(i = 0; i < nblock; i++) {
-    if(write(fd, buf, sizeof(buf)) != sizeof(buf)) {
-      printf("write %s failed\n", file);
-      exit(-1);
-    }
-  }
-  close(fd);
-}
-
-void
-readfile(char *file, int nbytes, int inc)
-{
-  char buf[BSIZE];
-  int fd;
-  int i;
-
-  if(inc > BSIZE) {
-    printf("readfile: inc too large\n");
-    exit(-1);
-  }
-  if ((fd = open(file, O_RDONLY)) < 0) {
-    printf("readfile open %s failed\n", file);
-    exit(-1);
-  }
-  for (i = 0; i < nbytes; i += inc) {
-    if(read(fd, buf, inc) != inc) {
-      printf("read %s failed for block %d (%d)\n", file, i, nbytes);
-      exit(-1);
-    }
-  }
-  close(fd);
-}
-
-int ntas(int print)
-{
-  int n;
-  char *c;
-
-  if (statistics(buf, SZ) <= 0) {
-    fprintf(2, "ntas: no stats\n");
-  }
-  c = strchr(buf, '=');
-  n = atoi(c+2);
-  if(print)
-    printf("%s", buf);
-  return n;
-}
-
-// Test reading small files concurrently
-void
-test0()
-{
-  char file[2];
-  char dir[2];
-  enum { N = 10, NCHILD = 3 };
-  int m, n;
-
-  dir[0] = '0';
-  dir[1] = '\0';
-  file[0] = 'F';
-  file[1] = '\0';
-
-  printf("start test0\n");
-  for(int i = 0; i < NCHILD; i++){
-    dir[0] = '0' + i;
-    mkdir(dir);
-    if (chdir(dir) < 0) {
-      printf("chdir failed\n");
-      exit(1);
-    }
-    unlink(file);
-    createfile(file, N);
-    if (chdir("..") < 0) {
-      printf("chdir failed\n");
-      exit(1);
-    }
-  }
-  m = ntas(0);
-  for(int i = 0; i < NCHILD; i++){
-    dir[0] = '0' + i;
-    int pid = fork();
-    if(pid < 0){
-      printf("fork failed");
-      exit(-1);
-    }
-    if(pid == 0){
-      if (chdir(dir) < 0) {
-        printf("chdir failed\n");
-        exit(1);
-      }
-
-      readfile(file, N*BSIZE, 1);
-
-      exit(0);
-    }
-  }
-  
-  int status = 0;
-  for(int i = 0; i < NCHILD; i++){
-    wait(&status);
-    if (status != 0) {
-      printf("FAIL: a child failed\n");
-      exit(1);
-    }  
-  }
-  
-  printf("test0 results:\n");
-  n = ntas(1);
-  if (n-m < 500)
-    printf("test0: OK\n");
-  else
-    printf("test0: FAIL\n");
-}
-
-// Test bcache evictions by reading a large file concurrently
-void test1()
-{
-  char file[3];
-  enum { N = 200, BIG=100, NCHILD=2 };
-  
-  printf("start test1\n");
-  file[0] = 'B';
-  file[2] = '\0';
-  for(int i = 0; i < NCHILD; i++){
-    file[1] = '0' + i;
-    unlink(file);
-    if (i == 0) {
-      createfile(file, BIG);
-    } else {
-      createfile(file, 1);
-    }
-  }
-  for(int i = 0; i < NCHILD; i++){
-    file[1] = '0' + i;
-    int pid = fork();
-    if(pid < 0){
-      printf("fork failed");
-      exit(-1);
-    }
-    if(pid == 0){
-      if (i==0) {
-        for (i = 0; i < N; i++) {
-          readfile(file, BIG*BSIZE, BSIZE);
-        }
-        unlink(file);
-        exit(0);
-      } else {
-        for (i = 0; i < N*20; i++) {
-          readfile(file, 1, BSIZE);
-        }
-        unlink(file);
-      }
-      exit(0);
-    }
-  }
-
-  int status = 0;
-  for(int i = 0; i < NCHILD; i++){
-    wait(&status);
-    if (status != 0) {
-      printf("FAIL: a child failed\n");
-      exit(1);
-    }  
-  }
-
-  printf("\ntest1 OK\n");
-}
-
-//
-// test concurrent creates.
-//
-void
-test2()
-{
-  int nc = 4;
-  char file[16];
-
-  printf("start test2\n");
-  
-  mkdir("d2");
-
-  file[0] = 'd';
-  file[1] = '2';
-  file[2] = '/';
-
-  // remove any stale existing files.
-  for(int i = 0; i < 50; i++){
-    for(int ci = 0; ci < nc; ci++){
-      file[3] = 'a' + ci;
-      file[4] = '0' + i;
-      file[5] = '\0';
-      unlink(file);
-    }
-  }
-
-  int pids[nc];
-  for(int ci = 0; ci < nc; ci++){
-    pids[ci] = fork();
-    if(pids[ci] < 0){
-      printf("test2: fork failed\n");
-      exit(1);
-    }
-    if(pids[ci] == 0){
-      char me = "abcdefghijklmnop"[ci];
-      int pid = getpid();
-      int nf = (ci == 0 ? 10 : 15);
-
-      // create nf files.
-      for(int i = 0; i < nf; i++){
-        file[3] = me;
-        file[4] = '0' + i;
-        file[5] = '\0';
-        int fd = open(file, O_CREATE | O_RDWR);
-        if(fd < 0){
-          printf("test2: create %s failed\n", file);
-          exit(1);
-        }
-        int xx = (pid << 16) | i;
-        for(int nw = 0; nw < 2; nw++){
-          // the sleep() increases the chance of simultaneous
-          // calls to bget().
-          sleep(1);
-          if(write(fd, &xx, sizeof(xx)) <= 0){
-            printf("test2: write %s failed\n", file);
-            exit(1);
-          }
-        }
-        close(fd);
-      }
-
-      // read back the nf files.
-      for(int i = 0; i < nf; i++){
-        file[3] = me;
-        file[4] = '0' + i;
-        file[5] = '\0';
-        // printf("r %s\n", file);
-        int fd = open(file, O_RDWR);
-        if(fd < 0){
-          printf("test2: open %s failed\n", file);
-          exit(1);
-        }
-        int xx = (pid << 16) | i;
-        for(int nr = 0; nr < 2; nr++){
-          int z = 0;
-          sleep(1);
-          int n = read(fd, &z, sizeof(z));
-          if(n != sizeof(z)){
-            printf("test2: read %s returned %d, expected %ld\n", file, n, sizeof(z));
-            exit(1);
-          }
-          if(z != xx){
-            printf("test2: file %s contained %d, not %d\n", file, z, xx);
-            exit(1);
-          }
-        }
-        close(fd);
-      }
-
-      // delete the nf files.
-      for(int i = 0; i < nf; i++){
-        file[3] = me;
-        file[4] = '0' + i;
-        file[5] = '\0';
-        //printf("u %s\n", file);
-        if(unlink(file) != 0){
-          printf("test2: unlink %s failed\n", file);
-          exit(1);
-        }
-      }
-
-      exit(0);
-    }
-  }
-
-  int ok = 1;
-
-  for(int ci = 0; ci < nc; ci++){
-    int st = 0;
-    int ret = wait(&st);
-    if(ret <= 0){
-      printf("test2: wait() failed\n");
-      ok = 0;
-    }
-    if(st != 0)
-      ok = 0;
-  }
-  if(ok) {
-    printf("\ntest2 OK\n");
-  } else {
-    printf("test2 failed\n");
-  }
-}
-
-//
-// generate big log transactions to check that bget() can
-// make use of any of the NBUF buffers for any block number.
-//
-void
-test3()
-{
-  int nc = 5;
-  char file[16];
-
-  printf("start test3\n");
-  
-  mkdir("d2");
-
-  file[0] = 'd';
-  file[1] = '2';
-  file[2] = '/';
-
-  int pids[nc];
-  for(int ci = 0; ci < nc; ci++){
-    pids[ci] = fork();
-    if(pids[ci] < 0){
-      printf("test3: fork failed\n");
-      exit(1);
-    }
-    if(pids[ci] == 0){
-      file[3] = 'a' + ci;
-      file[4] = '\0';
-      unlink(file);
-      int fd = open(file, O_CREATE | O_RDWR);
-      if(fd < 0){
-        printf("test3: create %s failed\n", file);
-        exit(1);
-      }
-      write(fd, "x", 1);
-      static char junk[12*512];
-      for(int i = 0; i < 12; i++){
-        sleep(1);
-        write(fd, junk, sizeof(junk));
-      }
-      exit(0);
-    }
-  }
-
-  int ok = 1;
-
-  for(int ci = 0; ci < nc; ci++){
-    int st = 0;
-    int ret = wait(&st);
-    if(ret <= 0){
-      printf("test3: wait() failed\n");
-      ok = 0;
-    }
-    if(st != 0)
-      ok = 0;
-  }
-
-  for(int ci = 0; ci < nc; ci++){
-    file[3] = 'a' + ci;
-    file[4] = '\0';
-    unlink(file);
-  }
-
-  if(ok) {
-    printf("\ntest3 OK\n");
-  } else {
-    printf("test3 failed\n");
-  }
-}

user/init.c

@@ -18,7 +18,6 @@ main(void)
 
   if(open("console", O_RDWR) < 0){
     mknod("console", CONSOLE, 0);
-    mknod("statistics", STATS, 0);
     open("console", O_RDWR);
   }
   dup(0);  // stdout

user/kalloctest.c

@@ -1,198 +0,0 @@
-#include "kernel/param.h"
-#include "kernel/types.h"
-#include "kernel/stat.h"
-#include "kernel/riscv.h"
-#include "kernel/memlayout.h"
-#include "kernel/fcntl.h"
-#include "user/user.h"
-
-#define NCHILD 2
-#define N 100000
-#define SZ 4096
-
-void test1(void);
-void test2(void);
-void test3(void);
-char buf[SZ];
-
-int countfree();
-  
-int
-main(int argc, char *argv[])
-{
-  test1();
-  test2();
-  test3();
-  exit(0);
-}
-
-int ntas(int print)
-{
-  int n;
-  char *c;
-
-  if (statistics(buf, SZ) <= 0) {
-    fprintf(2, "ntas: no stats\n");
-  }
-  c = strchr(buf, '=');
-  n = atoi(c+2);
-  if(print)
-    printf("%s", buf);
-  return n;
-}
-
-// Test concurrent kallocs and kfrees
-void test1(void)
-{
-  void *a, *a1;
-  int n, m;
-
-  printf("start test1\n");  
-  m = ntas(0);
-  for(int i = 0; i < NCHILD; i++){
-    int pid = fork();
-    if(pid < 0){
-      printf("fork failed");
-      exit(-1);
-    }
-    if(pid == 0){
-      for(i = 0; i < N; i++) {
-        a = sbrk(4096);
-        *(int *)(a+4) = 1;
-        a1 = sbrk(-4096);
-        if (a1 != a + 4096) {
-          printf("test1: FAIL wrong sbrk\n");
-          exit(1);
-        }
-      }
-      exit(0);
-    }
-  }
-  int status = 0;
-  for(int i = 0; i < NCHILD; i++){
-    wait(&status);
-    if (status != 0) {
-      printf("FAIL: a child failed\n");
-      exit(1);
-    }
-  }
-  printf("test1 results:\n");
-  n = ntas(1);
-  if(n-m < 10) 
-    printf("test1 OK\n");
-  else
-    printf("test1 FAIL\n");
-}
-
-
-// Test stealing
-void test2() {
-  int free0 = countfree();
-  int free1;
-  int n = (PHYSTOP-KERNBASE)/PGSIZE;
-  printf("start test2\n");  
-  printf("total free number of pages: %d (out of %d)\n", free0, n);
-  if(n - free0 > 1000) {
-    printf("test2 FAILED: cannot allocate enough memory");
-    exit(1);
-  }
-  for (int i = 0; i < 50; i++) {
-    free1 = countfree();
-    if(i % 10 == 9)
-      printf(".");
-    if(free1 != free0) {
-      printf("test2 FAIL: losing pages %d %d\n", free0, free1);
-      exit(1);
-    }
-  }
-  printf("\ntest2 OK\n");  
-}
-
-// Test concurrent kalloc/kfree and stealing
-void test3(void)
-{
-  uint64 a, a1;
-  int n, m;
-
-  m = ntas(0);
-  printf("start test3\n");
-  int pid;
-  
-  for(int i = 0; i < NCHILD; i++){
-    pid = fork();
-    if(pid < 0){
-      printf("fork failed");
-      exit(-1);
-    }
-    if(pid == 0){
-      if (i == 0) {
-        for(i = 0; i < N; i++) {
-          a = (uint64) sbrk(4096);
-          if(a == 0xffffffffffffffff){
-            // no freemem
-            continue;
-          }
-          *(int *)(a+4) = 1;
-          a1 = (uint64) sbrk(-4096);
-          if (a1 != a + 4096) {
-            printf("test3 FAIL: wrong sbrk\n");
-            exit(1);
-          }
-          if ((i + 1) % 10000 == 0) {
-            printf(".");
-          }
-        }
-        printf("child done %d\n", i);
-        exit(0);
-      } else {
-        while (1) {
-          int free0 = countfree();
-          int free1 = countfree();
-          if(free0 - free1 > 1) {
-            printf("test3 FAIL: losing pages %d %d\n", free0, free1);
-            exit(1);
-          }
-        }
-      }
-    }
-  }
-
-  int status = 0;
-  for(int i = 0; i < NCHILD-1; i++){
-    wait(&status);
-    if (status != 0) {
-      printf("a child failed\n");
-      exit(1);
-    }
-  }
-  kill(pid);
-
-  n = ntas(1);
-  if(n-m < 4000) 
-    printf("\ntest3 OK\n");
-  else
-    printf("test3 FAIL m %d n %d\n", m, n);
-}
-
-
-//
-// countfree() from usertests.c
-//
-int
-countfree()
-{
-  uint64 sz0 = (uint64)sbrk(0);
-  int n = 0;
-
-  while(1){
-    uint64 a = (uint64) sbrk(4096);
-    if(a == 0xffffffffffffffff){
-      break;
-    }
-    // modify the memory to make sure it's really allocated.
-    *(char *)(a + 4096 - 1) = 1;
-    n += 1;
-  }
-  sbrk(-((uint64)sbrk(0) - sz0));
-  return n;
-}

user/statistics.c

@@ -1,24 +0,0 @@
-#include "kernel/types.h"
-#include "kernel/stat.h"
-#include "kernel/fcntl.h"
-#include "user/user.h"
-
-int
-statistics(void *buf, int sz)
-{
-  int fd, i, n;
-  
-  fd = open("statistics", O_RDONLY);
-  if(fd < 0) {
-      fprintf(2, "stats: open failed\n");
-      exit(1);
-  }
-  for (i = 0; i < sz; ) {
-    if ((n = read(fd, buf+i, sz-i)) < 0) {
-      break;
-    }
-    i += n;
-  }
-  close(fd);
-  return i;
-}

user/stats.c

@@ -1,24 +0,0 @@
-#include "kernel/types.h"
-#include "kernel/stat.h"
-#include "kernel/fcntl.h"
-#include "user/user.h"
-
-#define SZ 4096
-char buf[SZ];
-
-int
-main(void)
-{
-  int i, n;
-  
-  while (1) {
-    n = statistics(buf, SZ);
-    for (i = 0; i < n; i++) {
-      write(1, buf+i, 1);
-    }
-    if (n != SZ)
-      break;
-  }
-
-  exit(0);
-}

user/user.h

@@ -1,7 +1,3 @@
-#ifdef LAB_MMAP
-typedef unsigned long size_t;
-typedef long int off_t;
-#endif
 struct stat;
 
 // system calls
@@ -26,17 +22,6 @@ int getpid(void);
 char* sbrk(int);
 int sleep(int);
 int uptime(void);
-#ifdef LAB_NET
-int bind(uint16);
-int unbind(uint16);
-int send(uint16, uint32, uint16, char *, uint32);
-int recv(uint16, uint32*, uint16*, char *, uint32);
-#endif
-#ifdef LAB_PGTBL
-int ugetpid(void);
-uint64 pgpte(void*);
-void kpgtbl(void);
-#endif
 
 // ulib.c
 int stat(const char*, struct stat*);
@@ -52,9 +37,6 @@ void* memset(void*, int, uint);
 int atoi(const char*);
 int memcmp(const void *, const void *, uint);
 void *memcpy(void *, const void *, uint);
-#ifdef LAB_LOCK
-int statistics(void*, int);
-#endif
 
 // umalloc.c
 void* malloc(uint);

user/xargstest.sh

@@ -0,0 +1,6 @@
+mkdir a
+echo hello > a/b
+mkdir c
+echo hello > c/b
+echo hello > b
+find . b | xargs grep hello